As a result of the fork I now have independent currency on both chains?

If I think that Bitcoin Cash will ultimately not succeed, I should sell into this P&D, right?

If you actually have the private keys to your bitcoin (ie. you have your bitcoin in bitcoin wallet software on your computer such as in the official client or the electrum client), and you had them at the time of the fork (Aug 1), then yes. If you had your bitcoins held by a 3rd party like an exchange, then it's up to them to decide whether they want to support a fork like bitcoin cash at all and credit it to your account.

correct. All indicators (miners not switching, 60% Korean volume, 0 dev support, plethora of FUD articles about core) are showing that it's a P&D and now is a great time to sell all your BCH back to BTC.

Yes.

Significantly so. The price of BTC alone is still more than BTC before the fork.

How do cryptocurrency adherents explain this? I mean, that value has to come from somewhere.

As I recall, when the fork just happened, the explanation was that the price of BCH was largely meaningless, because you couldn't actually withdraw them as cash, either directly or via BTC or other coins. You could only trade within confines of exchanges where they materialized. Did that change since then?

> How do cryptocurrency adherents explain this?

Speculators be speculatin'.

> I mean, that value has to come from somewhere.

Demand is constrained: only miners and those who bought BCC since Aug 1 fork have any BCC to sell. Most of us struggle with "hmm how do I recover/import my BTC wallet keys into BCC? Holy crap it's worth how much?!" And finally much of the BCC is semi-orphaned by the fact that they hold pre-fork currency but have no idea that BTC exists.

s/demand/supply/

Yes. BTC went up significantly after the fork, and BCH is also climbing.